Long known as Cupressus macrocarpa, the new taxon name (Hesperocyparis macrocarpa (Hartw.) Bartel) is not universally accepted.

Common Name: Monterey Cypress

General Information

Hesperocyparis macrocarpa is an evergreen tree growing up to 25 metres tall. The crown in young trees is columnar or cone-shaped, but becomes broad and spreading as the tree ages[]. The bole can be up to 170cm in diameter[]. A tall, straight tree in sheltered sites, it becomes twisted and contorted with many low branches when subject to constant sea breezes and salt spray[, ].
The plant is sometimes cultivated as a timber crop in the warm temperate to the tropical zones[]. It has been widely used in the past for hedging, especially before the advent of the 'Leyland Cypress', it is often planted to provide shelter from strong, especially maritime, winds and is also much grown as an ornamental - several cultivars have been developed[, ].
Hesperocyparis macrocarpa has a very restricted range and a small population, although this appears stable at present with most trees within protected areas safeguarded from further urban and other development. The plant is classified as 'Vulnerable' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

None known

Botanical References

, ,

Range

South-western N. America - California

Habitat

Restricted to a narrow coastal strip on rocky cliffs, slopes and headlands, forming pure stands or associated with Pinus radiata, in loam or sand over granitic rocks or in rock crevices[].

Properties

Weed Potential	Yes
Conservation Status	Vulnerable
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	25.00 m
Growth Rate	Fast
Pollinators	Wind
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Monterey cypress is a plant of a Mediterranean type of climate, with wet winters andf dry summers cooled by frequent fogs and within reach of ocean salt sprays. It has been cultivated successfully in the subtropics and at higher elevations in the tropics, where it can be grown at elevations up to 3,500 metres. It grows best in areas where annual daytime temperatures are within the range 20 - 32°c, but can tolerate 6 - 36°c[]. When dormant, the plant can survive temperatures down to about -14°c, but young growth can be severely damaged at -1°c[]. It prefers a mean annual rainfall in the range 900 - 1,400mm, but tolerates 700 - 1,600mm[].
Requires a sunny position[]. Thrives in a well-drained loamy or peaty soil[]. Very tolerant of hot dry conditions[]. Tolerates poor sandy soils[] but is then more subject to insect damage in a succession of dry seasons[]. Plants are not happy when growing on chalk, but they thrive on limestone[]. Prefers a pH in the range 5.5 - 7, tolerating 4.5 - 8.5[]. Very tolerant of maritime exposure[, , ] but plants are not very wind firm in shallow soils[]. Young trees require staking when planted in very exposed positions[].
The tree is often cultivated as an ornamental, shelter plant and timber crop. It has escaped from cultivation in many areas and has become established in the wild. It is classified as 'Invasive' in some Pacific Islands, New Zealand and Australia[].
New growth takes place from May to September and can be very vigorous when young with new shoots 1 metre long and increases in girth of 5cm or more a year even in old trees[]. Trees in a very exposed maritime position at Rosewarne in N. Cornwall were 12 metres tall after 30 years[].
Resents root disturbance, it is best planted out when the roots are in active growth in early autumn or spring[].
The cones ripen in their second year[]. They can remain closed on the tree for a number of years, opening after the heat of a forest fire to scatter their seeds which then germinate and grow quickly in the ashes of the fire[].
The crushed leaves have a strong scent of lemon verbena[].
Trees are notably susceptible to honey fungus[].

Edible Uses

None known

Medicinal

A decoction of the foliage has been used in the treatment of rheumatism[].

Agroforestry Uses:

A good fast growing hedge or shelterbelt tree, tolerating maritime exposure[, , ]. It can be trimmed so long as it is not cut back into old wood.

Other Uses

Wood - heavy, hard, strong, close-grained and very durable[]. Used for general construction[, ].
The wood makes a good fuel[].

Propagation

Seed - sow late winter in a cold frame and only just cover the seed[]. Three weeks cold stratification can improve germination rates[]. The seed usually germinates in 1 - 2 months at 20°c. The seedlings are very subject to damping off so should be watered with care and kept well-ventilated[]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. The seed can store for several years[].
Cuttings of almost ripe wood, September in a frost-proof frame[]. mid spring is the best time to take cuttings[].